Naoko Yasutani, known as Nao, is a sixteen-year-old girl whose family has recently moved back to Japan after 13 years in the United States. After a year that has involved a series of traumatic events, Nao starts writing about her experiences in a diary so that she can tell someone about her life—and the extraordinary life of her great-grandmother, Jiko Yasutani—before she commits suicide. Because Nao didn’t grow up in Japan, she identifies more as American than as Japanese and struggles to fit in when her family moves to Tokyo. She is badly bullied by her classmates, who fluctuate between physically torturing her and pretending she doesn’t exist. At home, her dad is suffering from serious depression and tries to kill himself by throwing himself in front of a train.

After a very difficult few months, Nao spends the summer with her great-grandmother at her temple in northern Japan. Jiko teaches Nao to clear her mind by practicing zazen, Zen Buddhist meditation, and helps her develop more confidence in herself. She also talks to Nao about her son Haruki, his interest in philosophy and French literature, and his tragic death as a kamikaze pilot in World War II. Nao even encounters her great-uncle for herself when his ghost visits during the holiday of Obon.